Have had my OSS can for a few months, made a few kills with it. It's on an LWRC 5.56. I'm no expert, but my experience has been the same as what everyone else has said. The weight is mostly back towards the grip, so while the gun weighs more, it isn't too objectionable. I actually prefer running this configuration better now. Also the minimal length change is great, not bad at all and easy to adjust to in a hunting situation. Runs dirtier than unsuppressed, but not by much. I'm sure it helps that it's a piston gun, too.
It's been quiet enough that I easily hear the "whop"of the bullet hitting home. For my money, it's been the single best modification to my gun I've ever made. Hope that helps.
